Preflop - not sure if I should 3bet at all. UTG might fold AQ and small PPs. But maybe AK is folding as well but not 100%.

BTN could have PPs often, also weaker Qx, or Ax.

Flop, if button has KQ then cbet is ok. But he might want to flaot maybe, but I am not sure if on this dry board he would do that.

On turn I might scare all the hands if I bet, so I checked and let him float. but y raise could not scare all hands as well. I guess I could just call turn, because only K on river is scare for me and then c/c the river. But would he bluff the K river, or a blnak river? With KQ he probably would cbh. Or is he calling my raise on turn with KQ? And KQ is only posible hand that can call my raise on turn I guess.

any Qx would call your turn c/rai, so I think going all-in with tptk is perfectly fine. You´re getting stacked anyway if he has there 88/55 or TT, so better to think how to stack his KQ, QJs and protect against 76s or maybe T9s and best play imo is to c/rai since that way you don´t have to face bad river card and can stack his worst hands by also protecting your hand

24/21 hand range generally can be very wide and depends a lot on the opponents. Even if you think he can´t call you too many worse hands on the turn I think shoving is better, since you can then balance out always shoving with draws so he then has to start b/c turn his 99 or JJ type hands or give you free card where you can improve your hand on the river.